Hi Nicolas, On 08/27/2012 05:48 PM, Nicolas THERY wrote: > Hello, > > On 2012-08-23 11:51, Sylwester Nawrocki wrote: >> This patch series introduces new image source class control - V4L2_CID_FRAMESIZE >> and vendor or device specific media bus format section. >> >> There was already a discussion WRT handling interleaved image data [1]. >> I'm not terribly happy with those vendor specific media bus formats but I >> couldn't find better solution that would comply with the V4L2 API concepts >> and would work reliably. > > What about Sakari's "Frame format descriptors" RFC[1] that would allow to > describe arbitrary pixel code combinations and provide required information > (virtual channel and data type) to the CSI receiver driver for configuring the > hardware? Thanks for reminding about this. The "Frame format descriptors" would not necessarily solve the main problem which I tried to address in this RFC. The sensor in question uses single MIPI-CSI data type frame as a container for multiple data planes, e.g. JPEG compressed stream interleaved with YUV image data, some optional padding and a specific metadata describing the interleaved image data. There is no MIPI-CSI2 virtual channel or data type interleaving. Everything is transferred on single VC and single DT. Such a frames need sensor specific S/W algorithm do extract each component. So it didn't look like the frame descriptors would be helpful here, since all this needs to be mapped to a single fourcc. Not sure if defining a "binary blob" fourcc and retrieving frame format information by some other means would have been a way to go. I also had some patches adopting design from Sakari's RFC, for the case where in addition to the above frame format there was captured a copy of meta-data, (as in the frame footer) send on separate DT (Embedded Data). And this was mapped to 2-planar V4L2 pixel format. Even then I used a sensor specific media bus code. In the end of the day I switched to a single-planar format as it had all what's needed to decode the data. And the were some H/W limitations on using additional DT. The frame format descriptors might be worth to work on, but this doesn't look like a solution to my problem and it is going to take some time to get it right, as Sakari pointed out. -- Regards, Sylwester -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
